NCDS4 (1981)

The 1981 survey differs from the three earlier NCDS follow-ups in that information was obtained from the subject (who was interviewed by a professional survey research interviewer) and from the 1971 and 1981 Censuses (from which variables describing area of residence were taken).

It is perhaps important to note that this fourth follow-up was preceded by a feasibility study designed to explore the practical problems associated with an adult follow-up; assess the likely level of response; and, in the light of this, and discussions with potential sponsors, prepare proposals for future surveys of the NCDS cohort. This work was sponsored by the Department of the Environment, who approached the National Children's Bureau in 1977, towards the end of the work on the third follow-up in order to examine the possibility of the Study continuing with funding from a number of government departments.

The feasibility study was completed at the end of 1978. Amongst other things it showed, with evidence from a specially commissioned survey, in which an attempt was made to trace, contact and interview a five percent random sample of those involved in one or more NCDS follow-ups, that it was possible to find the greater majority of those who had been involved with NCDS over the years, and that most were happy to continue to provide information on a wide variety of topics. Discussions with government departments revealed that there was a great deal of interest in a fourth and even later follow-ups. However, it was not until the spring of 1980 that agreement on the funding of the fourth follow-up was reached.

The 1981 Interview Survey

The target sample for the 1981 survey also differed. It consisted of all those who had participated in at least one of the earlier NCDS follow-ups, excluding those known to have emigrated or to have died. There was no attempt to include new immigrants, as there had been with the first three follow-ups.

Following initial tracing by the National Children's Bureau (NCB), details of names and addresses were passed to NOP Market Research Limited and Social and Community Planning Research who carried out further tracing and subsequent interviews. The survey was carried out between August 1981 and March 1982. Each interview took approximately 90 minutes.

Completed questionnaires were visually checked by NOP and SCPR and the data then transferred by them to computer. Following preliminary computer editing by NOP and SCPR more detailed checks were carried out by NCB. The majority of open-ended questions were coded by SCPR using coding frames developed by the Bureau research team. The remaining open-ended questions, including all those relating to health and health-related behaviour, were coded by NCB.

The cohort members were 23 years old at the time of the 1981 interview, and had reached a stage in their life cycle marked by major transitions - for example, from school or full-time further and higher education to work, from dependent status in their families of origin to independent status as members or heads of new households, from single status to partnership with marriage partners or cohabitees, and from childlessness to parenthood. During the interview survey detailed information was been sought from these young adults about:

  • Employment, unemployment and periods of out of the labour force (including details of economic status for each month since March 1974; dates and durations; occupation; industry; earnings; training; promotion, hours; job satisfaction; job choice; job behaviour; participation in government special schemes etc).
  • Apprenticeship and training (including details of dates and durations; trades and skills; courses and qualifications; and reasons for non-completion etc).
  • Post-school education (including details of dates and duration; courses; subjects; qualifications; failed courses; courses not leading to qualifications; planned courses; finance; literacy and numeracy problems etc).
  • Marriage, cohabitation and children (including details of dates of marriage(s) and cohabitation(s); age and prior status of partner(s); abortion and miscarriage; dates of birth and birth weight of children and experience of lone parenthood, etc).
  • Housing and household (including details of household composition; type and tenure of housing; amenities; housing costs; home ownership aspiration; leaving home; homelessness, etc).
  • Family income, savings and investment (including details of state benefits; other payments from outside the household; savings investments and inheritances).
  • Respondent reported health state and health related behaviour (including details of smoking, drinking, handicap, migraine, epilepsy, asthma and wheezy bronchitis, other conditions requiring regular medical supervision, accidents, hospital admittances and emotional problems).
  • Voluntary activity and leisure, etc (including details of the nature and frequency of activities; religion; voting behaviour; trade union membership; and newspaper readership).
  • Malaise Inventory (a 24 item inventory completed by the respondents at the completion of the interview. This is a measure indicating a tendency towards non-clinical depression developed by the Institute of Psychiatry from the Cornell Medical Index (Rutter and others, 1970)).

Area Data Based on the 1971 and 1981 Census

Following the completion of the 1981 survey additional data were obtained which summarise the characteristics of the area in which each cohort member was living, both at the time of the survey and at the time of the 1974 survey. These data, based on the Small Area Statistics (SAS) of both the 1971 and 1981 Census, were provided by CACI International (1971 and 1981 Census) and the ESRC Data Archive (1981 Census) and comprise the following:

Area data based on the 1971 Census 

This provides for each respondent, both at 16 (1974 address) and 23 (1981 address), the following:

  • Location codes - postcode, OPCS enumeration district, OPCS Census district, ward, constituency, pre-1974 district, post-1974 district, pre-1974 county, post-1974 county, standard region.
  • ACORN type - a classification of OPCS enumeration districts into 36 residential neighbourhood types. The classification is based on 40 census variable covering demographic structure, household composition, housing, socio-economic structure and residents' employment characteristics. These ACORN neighbourhood types can be classified into 11 ACORN groups. (Webber and Craig, 1978, 1979; CACI no date).
  • Constituency type - a classification of the 623 constituencies using the same 40 census variables which are the basis of ACORN. The classification is, however, different. Each constituency is allocated to one of 30 groups which can in turn be combined into 6 larger groupings. (Webber, 1978b).
  • Census ratios - these 19 ratios of Census counts, taken from the Small Area Statistics, provide summary area data descriptive of different aspects of the socio-economic structure, employment characteristics and housing environment for each respondent. They are recorded for both 1971 Census enumeration district (the smallest unit for which census statistics are available with an average population of about 460); and pre-1974 local authority.

Area data based on the 1981 Census 

This provides for each respondent, and for the 1981 address only:

  • Location codes - postcode, ward, district, county, standard region.
  • ACORN type at ward level - a classification of residential neighbourhoods into 38 types based on 41 variables from the 1981 Census encompassing demographic, housing and employment characteristics. The 38 neighbourhood types can be aggregated to give 11 neighbourhood groups.
  • Census counts - 331 counts taken from the Census Small Area Statistics relating to demographic, socio-economic, employment and housing characteristics which permit the derivation of summary measures describing different aspects of the area in which the respondent lives.